Outboard motor lubricating system



Feb T75, T195@ A. s. BosMA OUTBOARD MOTOR LUBRICATING SYSTEM 2sheets-sheet 1 Filed OCT.. l', 1944 at E 0J 5 INVENTOR.

ATTORNEYS.

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'Feba 7 E950 A. s, BQSMA 2,496,434

ouTBoARD MOTOR LUBRICATlNG SYSTEM Filed oct. 15, 1944 A2 shets-sneet 2gygy '5,

5 f INVENTOR EN i @gli/i3 Patented Feb. 7, 1950 UNITED STATES Pi'iTillNTOFFICE OUTBOARD IMOTOR LUBRICATING SYSTEM Alfred yS. Bosma, NewHolstein, Wis., assignor to Hart-Carter Company, Peoria, Ill., acorporation of Delaware Application AOctober 13, 1944, Serial No.558,560

koil in iva separate reservoir haslheretofore presented problems in anoutboard motor. One of said problems arises Afrom the lfact that 4anoutboard motoris `frequently tilted to a horizontal lposition While on aboat or while being manually carried or placed on its side while beingtransported in a vehicle. Another problem :is that of leakage of oilduring operation.

My patent,No. -2,458,051,issued January 1, 1949, shows -a desirable.form of four cycle outboard motor construction having a separate oilreservoir `and :which is `designed to overcome the 'abovementionedproblems.

It is, therefore, one of the objects of the present yinvention toprovide `an improved four cycle outboard motor construction v-having aseparate oil reservoir and oil feeding means, said reservoir being solocated and constructed with reference to the position of cooper-ating'parts that fthe motor may be tilted to Vall necessary positions orplaced on its rside without causing oil from the reservoir to enter thecylinder and start trouble, and said 4reservoir being so located thatsurplus oil will drain from the vvbearings back into the reservoirvdur-ing normal operation.

A further object of the invention is to provide vin a construction asabove described, improved means preferably including agear pump forleffectively feeding the o-il to the parts to Ybe lubricated.

Amorespecic object of the invention is to provide an outboard motorconstruction wherein a housing -for the vertical drive shaft is soshaped and yconstructed as to form `a reservoir for oil, there beingmeans for delivering oil from the reservoir to the crankcase and `for'draining surplus oil from the crankcase back into the reservoir. Thedrain'arrangement is so worked 'out in conjunction with the housingforming the reservoir that the motor may be tilted to a horizontalposition while on the boat 'or while being manually carried, or the`motor may be placed on vits :side 'or even inverted without permittingoil Vfrom the reservoir to Aenter the crankcase. The arrangement is suchthat the gear pump, which 4is employed for forcing the oil upwardly tothe crankcase, may be located in a position Where itis normallysubmerged in oil, Thus Vpriming of the gear pump is unnecessary.

A further object of the invention is to 'provide a construction as abovedescribed wherein the oil reservoir is so located that the oil thereinserves to lubricate the lower bearing for the rvertical drive shaft, thebottom bevel gears, and the bearings Afor the horizontal propellershaft. It is, therefore, unnecessary with this motor to utilize aspecial grease for lubricating the bottom vgealli C2156.

A further object of the Ainvention is to provide an outboard motorconstruction, as vabove described, wherein the oil reservoir is immersedin water during normal use to cool the oil and render operation of theengine moreeilicient.

A -still further object of the invention is to provide an outboard motorconstructiomas above descbribed, wherein there is a special sealadjacent the propeller which effectively prevents leakage of oil orentrance of water into the bottom .propeller yshaft housing.

With the above and other objects in View, the invention consists of theimproved outboard motor, and all its parts and combinations as set forthin the claims, and all equivalents thereof.

In the accompanying drawings, illustrating one complete -embodiment ofthe preferred form of the invention,

Fig. 1 Lis a vertical longitudinal sectional View through the improvedmotor;

Fig. l2 is a fragmentary vertical sectional view taken at right anglesto Fig. y1;

Fig. 3 is a sectional View taken approximately on the line 3--3 of Fig.1, on a larger scale, parts being broken away;

Fig, 4 is a sectional View taken on the line 4-4 of Fig, 1; and

Fig. 5 is a fragmentary sectional View taken on line 5 5 of Fig. 4.

Referring more particularly to the drawings, the power head isdesignated generally by the numeral 8 and includes an upper housingportion 9 and a lower housing lportion l0. The lower housing portion `IDforms the bottom for the crankcase 5.

There is also a vertical drive shaft housing designated by the numeral lI which comprises an upper lpart l2 and a lower part I3.

Bolts I4 secure the bottom housing i0 for the power head in position andalso secure the upper part l2 of the vertical drive shaft housing inassembled relationship, there being a bearing plate l5 in between themembers 10 and H.

The vertical drive shaft housing parts I2 'and I3 are suitably connectedwith a horizontal plate or n I6 therebetween, there being gaskets I1 andI8 at the joint. The fm I 6 serves as an anticavitation plate.

Within the power head 8 is a four cycle gasoline engine and in thepreferred embodiment the engine comprises two cylinders I9 and 20. Theremay, however, be a greater or a lesser number of cylinders. The cylinderI9 is equipped with two valves 2 I, one being an intake valve and theother being an exhaust valve, and the cylinder 20 is similarly equippedwith two valves 22. 'I'he ignition is provided by spark plugs 23 and 24.

Within the cylinders I9 and 20 are pistons 25 and 26 which are suitablyconnected in the usual manner by connecting rods 21 with the crankshaft28. The upper end of the crankshaft projects through a bearing 29 at thetop of the head and carries a y wheel 3D. The lower end of thecrankshaft is suitably journalled in a ball bearing assembly 3| receivedin a cup shaped portion of the housing portion I8. Below the ballbearing assembly is an oil seal 32. Suitably splined to the lower end ofthe crankshaft is a vertical drive shaft 33 which has its upper endportion rotatable in a bearing 34 supported in the bearing plate I5.Below the bearing 34 is an oil seal 35. A starting pulley 36 is suitablyassociated with the upper end portion of the vertical drive shaft 33.

The lower end of the vertical drive shaft 33 is journalled in a bearing31, and below the bearing 31 the lower housing portion I3 is formed witha gear chamber 38. In this chamber is a bevel gear 39 rigidly connectedto the lower end of the vertical drive shaft 33 and meshing with a bevelgear 40 rigidly connected to a horizontal propeller shaft 4I. The innerend of the propeller shaft is journalled in a bearing 42, and anintermediate proportion of said shaft is journalled in a bearing 43suitably mounted in a boss 44. The boss 44 is connected by bolts 45 withthe member I3 to close the gear chamber 38.

On the outer end of the horizontal propeller shaft 4I is the usualpropeller 46. Adjacent the inner side of the propeller and surroundingthe propeller shaft 4I within the boss 44 is a special seal. This sealcomprises a brass disc 41, a cup shaped disc 48 preferably of a phenolicplastic material, and a packing 49 preferably of synthetic rubber. Thevarious members forming the seal are held in effective position by acoil spring 50. This seal effectively prevents escape of oil from thechamber 38, as well as entrance of water to said chamber.

Suitably connected to the lower side of the horizontal fin I6 is a gearpump 5I. This gear pump is driven by the vertical drive shaft 33 and isadapted to pump oi1 from the housing portion I3, through an inlet tube52, and deliver said oil under pressure upwardly through a tube 53 tothe lower end of a bearing 54 for the cam shaft 55. As is clearly shownin Figs. l and 2, the bearing 54 is formed in a horizontal partition 58,and said partition has portions which slope toward an outlet opening 56so that oil which drains from the crank case will be directed into theopening 56 and into a drain tube 51. The drain tube 51 extendsdownwardly to a point intermediate the length of the drive shaft housingand terminates in an open end 58. When the motor is in normal operatingposition the open end of the drain tube 58 is well above the normallevel 59 of oil in the reservoir.

Oil delivered by the pump I through the delivery tube 53 enters a duct60 in the cam shaft and flows upwardly through this duct to lubricatethe top bearing BI for the cam shaft. The majority of the oil from theduct 60, however, is sprayed out of openings 62 in the cam shaft ontothe connecting rod bearings.

The cam shaft is provided with a series of cams 63 for operating theintake and exhaust valves 2| and 22. Ihe cam shaft is driven by gears 64and 65, and the former is driven by the crankshaft.

The exhaust conduits from the motor are suitably connected to upperopenings 66 of an exhaust tube 61, and the lower end of the exhaust tubeis open, as at E8, to discharge below the water level.

A pin 69, which is supported on the exterior of the drive shaft housingII, extends through a pivot sleeve 10. Connected to the sleeve is theusual clamp 1I for removably securing the motor to a boat. The pin 69 ispivotal within the sleeve 10 to permit steering movement, and the entiremotor is swingable on the pin 12 toward a horizontal inoperativeposition on the boat. In use of the device, the novel vhousing for thevertical drive shaft forms a reservoir for motor oil. This reservoirmust be lled to approximately the level indicated at 59 in Fig. 1. Whenthe motor is in normal operating position, oil in the reservoir willfiow downwardly through the openings 13 in the horizontal plate I6 intothe reservoir portion 14 of the lower housing part I3 to fill theportion 14. Oil from the reservoir portion 14 will lubricate the bearing31 and will also pass through one or more holes 15 into the gear chamber38 to lubricate the bevel gears 39 and 40, as well as the bearings forthe propeller shaft 4I. The special seal 41 will effectively preventloss of any oil from the chamber 38 to the exterior.

The motor, of course, operates on gasoline undiluted with motor oil andduring operation the gear'pump will be operated by the drive shaft 33.This will cause continuous pumping of oil from the lower chamber 14upwardly through tubes 52 and 53 into the cam shaft duct 60 to lubricatethe motor. Surplus oil from the crankcase 1 will continually drain backinto the oil servoir through the opening 56 and drain tube The verticaldrive shaft housing I I is so shaped and is of such size, and the lowerend 58 of the drain tube is so located, that when the motor is swungupwardly on the boat on the pivot 12 to an inoperative position, or whenthe motor is placed on either side, the oil in the oil reservoir willflow the length of the drive shaft housing portion II and the level willalways be below the end 58 of the drain tube 51. Thus no oil can flowinto the crankcase through the drain tube when the motor is in any oneof thesehorizontally disposed positions.

Even 'if the motor is completely inverted, the oil in the reservoir willquickly fiow to the enlarged upper end portion of the drive shafthousing II and the open end 58 of the drain tube will be above the levelof the oil while the motor is in inverted position.

With the particular arrangement above described, a four cycle engine maybe successfully employed for an outboard motor without any inconvenienceresulting from the oil which it is necessary to have in the oilreservoir. The gear pump 5I is advantageously located in a positionwhere it is normally submerged in the oil, and this renders primingunnecessary. Furthermore, the lubrication of the bevel gears andpropeller shaft bearings by the same oil which lubricates the engineitself, renders the use of a separate greasing arrangement at the lowerend unnecessary. During use of the motor, the oil in the reservoir isalways submerged in the water and is effectively cooled. This cooling ofthe oil is transmitted to the engine as the oil is used to lubricate thelatter. As a result the engine is maintained at a cool runningtemperature to increase its efficiency of operation.

While the preferred embodiment includes the use of a four cycle engine,the features of `the present invention are suitable for use inconnection with any engine in which oil is carried in a crankcase.Various other changes, modifications and adaptations may be made withoutdeparting from the spirit of the invention, and all of such changes arecontemplated as may come within the scope of the claims.

What I claim is:

1. In an outboard motor having a top power head and including acombustion engine having a crankcase in said power head, a-bottom forsaid crankcase, a vertical drive shaft depending from said head anddriven by said engine, an elongated vertical housing for said verticaldrive shaft connected at its upper end -to the power head below thecrankcase bottom, a portion of said housing which surrounds the lowerpart of the vertical drive shaft forming a reservoir for f motor oilwhen the motor is in normal operat- `ing position, means for deliveringoil from said reservoir to said crankcase, and a return conduit forsurplus oil from the crankcase having a discharge end locatedintermediate the length of the drive shaft housing and above the levelof oil therein when the motor is in normal operating position.

2. In an outboard motor having a top power head and including acombustion engine having a crankcase in said power head, a bottom forsaid crankcase, a vertical drive shaft depending from said head anddriven by said engine, an elongated vertical housing for said verticaldrive shaft connected at its upper end to the power head below thecrankcase bottom, a portion of said housing which surrounds the lowerpart of the vertical drive shaft forming a reservoir for motor oil whenthe motor is in normal operating position, means for delivering oil fromsaid reservoir to said crankcase, and a return conduit for surplus oilfrom the crankcase having a discharge end located intermediate thelength of the drive shaft housing and above the level of oil thereinwhen the motor is in normal operating position, the drive shaft housinghaving a cross sectional area of such size and the discharge end of thereturn conduit being so located that there is space above the front wallof the housing sufficient to accommodate all oil normally in thecrankcase at a level beneath the discharge end of the return conduitwhen the motor is swung .to an inoperative position on a boat.

3. In an outboard motor having a top power head and including acombustion engine having a crankcase in said power head, a bottom forsaid crankcase, a vertical drive shaft depending from said head anddriven by said engine, an elongated vertical housing for said verticaldrive shaft connected at its upper end to the power head below thecrankcase bottom, a portion of said housing which surrounds the lowerpart of the vertical drive shaft forming a reservoir for motor oil whenthe motor is in normal operating position,

means for delivering oil from said reservoir to said crankcase, and areturn conduit for surplus oil from the crankcase having a discharge endlocated intermediate the length of the drive shaft housing and above thelevel of oil therein when the motor is in normal operating position,there being sufficient space in the upper portion of the drive shafthousing above the discharge end of the return conduit to accommodate alloil normally in the crankcase when the motor is inverted, with saiddischarge end projecting above the oil level.

4. In an outboard motor having a top power head and including acombustion engine having a crankcase in said power head, a bottom forsaid crankcase, a vertical drive shaft depending from said head anddriven by said engine, an elongated vertical housing for said Verticaldrive shaft connected at its upper end to the power head below thecrankcase bottom, a portion of said housing forming a reservoir formotor oil when the motor is in normal operating position, means fordelivering oil from said reservoir to said crankcase, and an elongatedreturn conduit for surplus oil from the crankcase having a discharge endlocated a substantial distance below the bottom of the crankcase andabove the level of oil in the reservoir when the motor is in normaloperating position.

5. In a normally vertically disposed outboard motor having a top powerhead and including a combustion engine having a crankcase in said head,a drive shaft housing below said crank case forming a reservoir formotor oil and having sidewalls, means for delivering oil from saidreservoir to said crankcase for lubricating purposes and an elongatedconduit extending into said housing for returning surplus oil from thecrankcase to said reservoir, the outlet end of said conduit beinglocated intermediate the length of said drive shaft housing and spacedfrom the sidewalls thereof 6. In a normally vertically disposed outboardmotor having a top power head and including a combustion engine having acrankcase in said head, a drive shaft housing below said crankcaseforming a reservoir for motor oil and having a forward wall portion anda rear wall portion, means for delivering oil from said reservoir tosaid crankcase for lubricating purposes, and an elongated conduitextending into said housing for returning surplus oil from the crankcaseto said reservoir, the outlet end of said conduit being locatedintermediate the length of the drive shaft housing and positioned closerto the rear wall thereof than to the forward wall.

ALFRED S. BOSMA.

REFERENCES CITED The following references are of record in the iile ofthis patent:

UNITED STATES PATENTS Number Name Date 1,446,775 Wahl Feb. 27, 19231,822,573 Fitzgerald Sept. 8, 1931 2,053,425 Else Sept. 8, 19362,289,124 Karey July 7, 1942 2,346,148 Bosma Apr. 11, 1944 FOREIGNPATENTS Number Country Date 432,035 Great Britain July 18, 1935

